如何从地图上获取钥匙

I'm working on go template. Having some map in . I know how to get the value, as long as I know the key.

"Map value: {{ printf "%s" .key1 }}"

How to get key name from inside the template? I would expect maybe something like

"Map key: {{ printf "%s" (keys .)[0] }}"

As @Adrian commented:

{{ range $key, $val := . }}
key: {{ $key }}; value: {{ $val }}
{{ end }}

But it was hard to figure it out just from range documentation